ROTATOR CUFF TEAR ARTHROPATHY (GLENOHUMERAL OSTEOARTHRITIS WITH MASSIVE ROTATOR CUFF TEAR)

Rotator cuff tear arthropathy was initially described by Neer and consists of a massive irreparable rotator cuff tear combined with glenohumeral arthritis and, in the late stages, humeral head osteonecrosis.² This entity has gradually expanded to include all patients with massive rotator cuff tears and glenohumeral arthritis, even in the absence of humeral head osteonecrosis. Although we believe that rotator cuff tear arthropathy as described by Neer and glenohumeral osteoarthritis with a massive rotator cuff tear are two distinct entities, the clinical scenarios are sufficiently similar that we consider them together both in our practice and in this textbook.

Rotator cuff tear arthropathy (glenohumeral osteoarthritis with a massive rotator cuff tear) is the single most common indication for which we per-form reverse shoulder arthroplasty. This indication accounts for nearly half of our cases of reverse shoulder arthroplasty.

Clinical Findings

Clinical findings in patients with glenohumeral osteoarthritis and a massive rotator cuff tear are variable and depend on both the degree of arthritis and the specific tendons of the rotator cuff that are torn. Most patients demonstrate some glenohumeral crepitus with stiffness. Additionally, acromiohumeral crepitus may be present.

Testing of the individual rotator cuff tendons will typically demonstrate obvious insufficiency. Rotator cuff insufficiency may involve the posterior superior rotator cuff (supraspinatus, infraspinatus, teres minor), the anterior superior rotator cuff (supraspinatus, subscapularis), or the entire rotator cuff. Additionally, the long head of the biceps tendon is often ruptured, as demonstrated by the characteristic deformity of the upper part of the arm. Chapter 7 details clinical testing of the rotator cuff.

Imaging Findings

Plain radiography demonstrates loss of the normal glenohumeral joint space. Humeral head osteophytes may or may not be present. Static migration of the humeral head is almost always present. In patients with insufficiency of the posterior superior rotator cuff, the humeral head migration occurs in a superior direction (Fig. 24-4). In patients with insufficiency of the anterior superior rotator cuff, static anterior migration may be apparent on just the axillary radiograph (Fig. 24-5). Less frequently, the patient may demonstrate only dynamic migration of the humeral head as a result of rotator cuff insufficiency. Acromial changes on radiographs of patients with no apparent static superior humeral head migration may show evidence of this dynamic instability (Fig. 24-6). Patients with osteoarthritis and a massive rotator cuff tear will frequently have osseous wear on the undersurface of the acromion, on the superior glenoid, or on both (Fig. 24-7). Less frequently, insufficiency fractures of the acromion may be caused by wear (Fig. 24-8). These stress fractures, however, do not contraindicate use of a reverse prosthesis.

Figure 24-4 Radiograph demonstrating superior migration of the humeral head in a patient with osteoarthritis and a massive rotator cuff tear involving the posterior superior rotator cuff.

Figure 24-5 Axillary radiograph of a patient with static anterior migration of the humeral head caused by chronic anterior superior rotator cuff insufficiency.

Figure 24-6 Acromial changes mirroring the radius of curvature of the humeral head in a patient with chronic rotator cuff insufficiency and only mild chronic humeral head superior migration.

Figure 24-7 Acromial wear in a patient with rotator cuff tear arthropathy.

Figure 24-8 A and B, Insufficiency fracture of the acromion (arrows) in a patient with rotator cuff tear arthropathy.

Secondary imaging studies (computed tomographic arthrography, magnetic resonance imaging) will always show rotator cuff tears involving more than one tendon (Fig. 24-9). The rotator cuff muscle belly of the torn tendons shows fatty infiltration (Fig. 24-10). In cases with long-standing rotator cuff tears involving the infraspinatus in which the teres minor is intact, the teres minor muscle belly may demonstrate compensatory hypertrophy (Fig. 24-11).

Figure 24-9 Computed tomographic arthrogram demonstrating a massive rotator cuff tear with glenohumeral arthritis.

Figure 24-10 Computed tomographic arthrogram demonstrating severe fatty infiltration of the infraspinatus (asterisk). Compare with the normal subscapularis.

Figure 24-11 Computed tomographic arthrogram demonstrating hypertrophy of the teres minor in a patient with infraspinatus insufficiency (asterisk).

Secondary imaging studies can confirm osseous wear (glenoid, acromion) in patients with glenohumeral osteoarthritis and a massive rotator cuff tear. Coronal sections of computed tomography or magnetic resonance imaging have been used to classify superior glenoid wear (Fig. 24-12).³

Figure 24-12 Classification of superior glenoid wear. A, E0 represents normal glenoid morphology. B, E1 represents central glenoid wear. C, E2 represents superior glenoid wear with superior biconcavity. D, E3 represents severe superior glenoid wear with a superiorly oriented glenoid morphology.

(From Oudet D, Favard L, Lautmann S, et al: La prosthèse d’épaule Aequalis dans les omarthroses avec rupture massive et non réparable de la coiffe. In Walch G, Boileau P, Molé D [eds]: 2000 Prosthèses d’Epaule … Recul de 2 à 10 Ans. Paris, Sauramps Medical, 2001, pp 241-246.)